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authorAmaury Decrême <amaury.decreme@gmail.com>2013-01-29 01:21:08 +0400
committerWolfram Sang <wolfram@the-dreams.de>2013-02-11 18:59:39 +0400
commita6e7d0efe0e21091682f62c4a72707a1adeef8ea (patch)
treee4b28da46a07d0f7ba310db039be686dd64325d4 /drivers/i2c
parent499b9194ad7b7b6d7c06b01005508e5bcf3c8980 (diff)
downloadlinux-a6e7d0efe0e21091682f62c4a72707a1adeef8ea.tar.xz
i2c: sis630: use hex to constants for SMBus commands
This patch replaces hexadecimal values by constants for SMBus commands. Signed-off-by: Amaury Decrême <amaury.decreme@gmail.com> Reviewed-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-sis630.c45
1 files changed, 31 insertions, 14 deletions
diff --git a/drivers/i2c/busses/i2c-sis630.c b/drivers/i2c/busses/i2c-sis630.c
index e152d36b94ac..b2fa7415f7e4 100644
--- a/drivers/i2c/busses/i2c-sis630.c
+++ b/drivers/i2c/busses/i2c-sis630.c
@@ -81,6 +81,21 @@
#define SMB_COUNT 0x07 /* byte count */
#define SMB_BYTE 0x08 /* ~0x8F data byte field */
+/* SMB_STS register */
+#define BYTE_DONE_STS 0x10 /* Byte Done Status / Block Array */
+#define SMBCOL_STS 0x04 /* Collision */
+#define SMBERR_STS 0x02 /* Device error */
+
+/* SMB_CNT register */
+#define MSTO_EN 0x40 /* Host Master Timeout Enable */
+#define SMBCLK_SEL 0x20 /* Host master clock selection */
+#define SMB_PROBE 0x02 /* Bus Probe/Slave busy */
+#define SMB_HOSTBUSY 0x01 /* Host Busy */
+
+/* SMBHOST_CNT register */
+#define SMB_KILL 0x20 /* Kill */
+#define SMB_START 0x10 /* Start */
+
/* register count for request_region
* As we don't use SMB_PCOUNT, 20 is ok for SiS630 and SiS964
*/
@@ -140,12 +155,14 @@ static int sis630_transaction_start(struct i2c_adapter *adap, int size, u8 *oldc
int temp;
/* Make sure the SMBus host is ready to start transmitting. */
- if ((temp = sis630_read(SMB_CNT) & 0x03) != 0x00) {
- dev_dbg(&adap->dev, "SMBus busy (%02x).Resetting...\n",temp);
+ temp = sis630_read(SMB_CNT);
+ if ((temp & (SMB_PROBE | SMB_HOSTBUSY)) != 0x00) {
+ dev_dbg(&adap->dev, "SMBus busy (%02x). Resetting...\n", temp);
/* kill smbus transaction */
- sis630_write(SMBHOST_CNT, 0x20);
+ sis630_write(SMBHOST_CNT, SMB_KILL);
- if ((temp = sis630_read(SMB_CNT) & 0x03) != 0x00) {
+ temp = sis630_read(SMB_CNT);
+ if (temp & (SMB_PROBE | SMB_HOSTBUSY)) {
dev_dbg(&adap->dev, "Failed! (%02x)\n", temp);
return -EBUSY;
} else {
@@ -160,16 +177,16 @@ static int sis630_transaction_start(struct i2c_adapter *adap, int size, u8 *oldc
/* disable timeout interrupt , set Host Master Clock to 56KHz if requested */
if (high_clock)
- sis630_write(SMB_CNT, 0x20);
+ sis630_write(SMB_CNT, SMBCLK_SEL);
else
- sis630_write(SMB_CNT, (*oldclock & ~0x40));
+ sis630_write(SMB_CNT, (*oldclock & ~MSTO_EN));
/* clear all sticky bits */
temp = sis630_read(SMB_STS);
sis630_write(SMB_STS, temp & 0x1e);
/* start the transaction by setting bit 4 and size */
- sis630_write(SMBHOST_CNT,0x10 | (size & 0x07));
+ sis630_write(SMBHOST_CNT, SMB_START | (size & 0x07));
return 0;
}
@@ -183,7 +200,7 @@ static int sis630_transaction_wait(struct i2c_adapter *adap, int size)
msleep(1);
temp = sis630_read(SMB_STS);
/* check if block transmitted */
- if (size == SIS630_BLOCK_DATA && (temp & 0x10))
+ if (size == SIS630_BLOCK_DATA && (temp & BYTE_DONE_STS))
break;
} while (!(temp & 0x0e) && (timeout++ < MAX_TIMEOUT));
@@ -193,12 +210,12 @@ static int sis630_transaction_wait(struct i2c_adapter *adap, int size)
result = -ETIMEDOUT;
}
- if (temp & 0x02) {
+ if (temp & SMBERR_STS) {
dev_dbg(&adap->dev, "Error: Failed bus transaction\n");
result = -ENXIO;
}
- if (temp & 0x04) {
+ if (temp & SMBCOL_STS) {
dev_err(&adap->dev, "Bus collision!\n");
result = -EAGAIN;
}
@@ -217,8 +234,8 @@ static void sis630_transaction_end(struct i2c_adapter *adap, u8 oldclock)
* restore old Host Master Clock if high_clock is set
* and oldclock was not 56KHz
*/
- if (high_clock && !(oldclock & 0x20))
- sis630_write(SMB_CNT,(sis630_read(SMB_CNT) & ~0x20));
+ if (high_clock && !(oldclock & SMBCLK_SEL))
+ sis630_write(SMB_CNT, sis630_read(SMB_CNT) & ~SMBCLK_SEL);
dev_dbg(&adap->dev, "SMB_CNT after clock restore 0x%02x\n", sis630_read(SMB_CNT));
}
@@ -270,7 +287,7 @@ static int sis630_block_data(struct i2c_adapter *adap, union i2c_smbus_data *dat
we must clear sticky bit.
clear SMBARY_STS
*/
- sis630_write(SMB_STS,0x10);
+ sis630_write(SMB_STS, BYTE_DONE_STS);
}
rc = sis630_transaction_wait(adap,
SIS630_BLOCK_DATA);
@@ -312,7 +329,7 @@ static int sis630_block_data(struct i2c_adapter *adap, union i2c_smbus_data *dat
dev_dbg(&adap->dev, "clear smbary_sts len=%d i=%d\n",len,i);
/* clear SMBARY_STS */
- sis630_write(SMB_STS,0x10);
+ sis630_write(SMB_STS, BYTE_DONE_STS);
} while(len < data->block[0]);
}